This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
A public resolver answers queries for anyone who sends them. The benchmark compares resolvers you name. It is a measurement of answers, not a permission to bypass a policy on a network you do not run.
Write what you are choosing for: your own clients, a lab, or a guest network you operate. Filtering, logging, and the anycast location are the differences that matter. Speed alone is not the policy.
If the network you administer already requires its own resolver, a public resolver on a client is a change with an owner. It is not a private trick. Do not point a device at a resolver to get around a control you do not administer.
example.com is a fine name to compare. Do not benchmark by querying names you have no reason to look up in bulk.
The change you can finish
Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.
Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.
- Name the clients you administer.
- Pick the resolvers you will compare.
- Read filtering and logging, not only time.
- Write the choice.
- Do not use it to evade a foreign network.
- Do not change every client in this hour.
Mistakes that outlive the command
How to Choose a Public DNS Resolver goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A resolver chosen to bypass a network you do not administer.
- Speed as the only column.
- A bulk list of other people's names.
- Changing production clients during the reading.
- No owner for the choice.
Decisions to write down
One decision for How to Choose a Public DNS Resolver: The clients are yours. Logging and filtering are written. The choice has an owner. No evasion is the goal. And clients were not all changed.
Checks before you call it done
Confirm this before you call the change done: The client group is named. Two resolvers were compared. The choice is one sentence. No foreign control was bypassed. And no mass change was made. If one of those fails, stop.
| Question | Why it is in the note |
|---|---|
| Who are the clients? | A resolver for a network you do not administer is out of scope. |
| What is logged? | A faster answer can still be the wrong policy. |
| Who changes the clients? | The reading hour does not push the choice. |
Before you leave the device
How to Choose a Public DNS Resolver ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.
0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.
One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature waits for its own page.
If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied config produces a device nobody can rebuild. Restore the copy you took first.
A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.
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